1. Technical Field
The present invention relates to gate stacks, and more particularly, to a gate stack of a transistor wherein the top region of the gate stack is less likely to break off than the top region of a typical gate stack during the fabrication of the transistor.
2. Related Art
A typical fabrication process of a transistor can start with the formation of a gate stack on a semiconductor substrate. Then, the gate stack can be used to define the source/drain regions of the transistor in the substrate. Eventually, the gate stack becomes the gate of the transistor. There is always a need to reduce the resistance of the gate of the transistor to improve the performance of the transistor.
Therefore, there is a need for a novel gate stack whose resistance is relatively lower than that of the prior art. Also, there is a need for a method for forming the novel gate stack.